Book Reviews

EDWIN HASLAM Plant Polyphenob-Vegetable Tannins Revisited Cambridge University Press, Cam- bridge, 1989. f37.50.

This book is one of the first volumes to be published in a new series of monographs with the general title of The Chemistry and Pharmacology of Natural Products, ed. by J. D. Phillipson, D. C. Ayres and H. Baxter. Since the publication of the author’s first book, Chemistry of Vegetable Tannins, in 1966, the chemistry of polyphenols has progressed to a stage where the structure of these complex molecules can be much more precisely defined. Polyphenols are important in the food and leather tanning industries, herbal teas and traditional medicines.

The book has four chapters. In the first, the history of the study of polyphenols is outlined together with their traditional uses. The astringency of polyphenols is defined and the chemical nomenclature to be used throughout the subsequent chapters is clearly established. The chemistry of polyphenols is discussed in the next two chapters were proanthocyanidins and gallic acids are considered. These chapters discuss in detail present knowledge of the biosynthesis and complex chemistry of these groups and their structural elucidation. The final chapter considers polyphenol complex- ing with proteins and polysaccharides. The importance of reversible complex-

ing with proteins, a process which underlies the phenomenon of astrin- gency, is considered in detail as is irreversible complexing . This latter form of complex being important in plant damage and in fermentation processes. Finally, the phenomenon of astringency in its various forms is discussed in detail.

The book is well referenced and must be considered a requirement for any student embarking on a research career in this area or for a would-be phytochemist. The book will also be of interest to chemists working in com- mercial areas where a working knowl- edge of the chemistry of polyphenols is useful.

MARGARET ROBERTS Department of Pharrnacognosy

University of London London

UK

LISELOTTE LANGHAMMER Bildatlas zur mikroskopischen Analytik pflanzlicher Arzneidrogen. (Illustrated atlas for the microscopical analysis of medicinal plants.) Student Edition. W. de Gruyter, Berlin. 1989. 241 pp.

This microscopical atlas contains al- most all those plant drugs encountered both in herbal medicine and as raw materials for the preparation of ex- tracts, including some not found illustrated anywhere else, such as Drosera, Carlina acaulis, Nerium oleander, except perhaps in micro-

scopical guides now out of print. Its purpose is to identify and authenticate plant material and it succeeds ad- mirably, mainly because of the quality of the microscopical mounts and photography, both of which are excellent.

The book is arranged in plant families, a useful division since it accentuates similarities and differences between related plant drugs. There is a good index at the end in which plant parts such as roots, barks, leaves etc are grouped together, along with a plant family index, a botanical Latin name index and a German drug name index.

There is a short macroscopical and microscopical description of each drug, including odour and taste, followed by the photographs, some taken of pow- dered samples and some of sections, all stained to emphasize important fea- tures where appropriate. There is also a mention of possible adulterants or substitutions, but there are no micro- scopical descriptions of these. Details are rather brief, but the photographs are clear and self-explanatory. For this reason it does not matter too much to non-German speakers that the book is available only in German; it would still be useful to anyone involved in the microscopical analysis of plant drugs.

ELIZABETH M. WILLIAMSON University of London

London UK

ii PHYTOTHERAPY RESEARCH, VOL. 4, NO. 4, 1990 0 1990 by John Wiley & Sons, Ltd.